The invention relates to a hydraulic system for actuating a belt-driven conical-pulley transmission of a vehicle, the transmission having a variably adjustable transmission ratio and including a torque sensor, the hydraulic system having at least one hydraulic energy source for supplying the torque sensor with working medium by a pump flow of the hydraulic energy source.
An object of the invention is to provide a hydraulic system in which losses that occur in operating the hydraulic energy source can be reduced.